The ArkFab Open Source Living Machine Series

Living machines are conventionally known to be engineered biological systems that treat waste water. ArkFab living machines extend this definition to convert any kind of organic waste into value-added products, like food, fuel, biomaterials, or ecosystem services like wastewater treatment.

The first draft of living machine designs for ArkFab are completed! I'm working with the Georgia Tech Research Institute and the Center for Biologically Inspired Design to build two prototype living machines for upcycling urban waste biomass into food, fuel, and biomaterials. The Truly Living Well Center for Urban Agriculture has generously offered space at their 4 acre Wheat Street Urban Farm site to build the first two prototypes.

These living machines will be used to convert spent grain from the local Sweetwater Brewery Company, coffee grounds from coffee shops, and woodchips from municipal arborists, into mushrooms, fresh fish, salad greens, and vermicompost. The designs and a guidebook for building these low-cost living machines will be published under an open source license for free distribution and replication. By building collaborative partnerships with other organizations like Growing Power in Milwaukee and Chicago and The Food Project in Massachusetts we can establish a national research network for accessible urban agriculture and waste management solution.

Spore v.0.1 is a draft prototype for a mushroom grow house that converts spent grain, spent coffee grounds, and other urban waste biomass into mushrooms and mushroom compost. The compost is then sent to the aquaponics living machine, Sol v.0.1 for further processing into earthworms, fish, and salad greens.

Growing Power Aquaponics System Assembly DiagramSol v.0.1 is based on designs for an aquaponics system from Growing Power. Theirs is a tested system that we can learn and build off of. By working with Growing Power we can identify current issues and make improvements with our implementation. This system uses vermicomposting to produce earthworms from the mushroom compost. These worms are then fed to tilapia which are held in tanks beneath the stacked planting beds. Effluent from the tilapia is then pumped through a biofilter that settles out suspended solids and converts toxic ammonia (to fish) into nitrates and nitrites for the plants. The salad greens grow in this water which then falls over the planting beds and in the process, increases its dissolved oxygen.

The preliminary budget for these two living machines comes well below $10,000. Currently, the costs should be about $6,000. After seeing a few more greenhouse I realized that a wood frame structure might be easier and cheaper to build than the bent steel frame structure that I have in these diagrams so expect the final designs to be somewhat different.

Check out the living machines proposal .pdf for more information.